> static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc)
> {
> struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
> - int band = bitmap2band[priv->bitmap];
> + struct sk_buff *skb = NULL;
> + int band;
>
> - if (band >= 0) {
> - struct qdisc_skb_head *qh = band2list(priv, band);
> + for (band = 0; band < PFIFO_FAST_BANDS && !skb; band++) {
> + struct skb_array *q = band2list(priv, band);
>
> - return qh->head;
> + skb = __skb_array_peek(q);
> + if (!skb)
> + continue;
> }
This explicit continue is not needed.
> static void pfifo_fast_reset(struct Qdisc *qdisc)
> {
> - int prio;
> + int i, band;
> struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
>
> - for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
> - __qdisc_reset_queue(band2list(priv, prio));
> + for (band = 0; band < PFIFO_FAST_BANDS; band++) {
> + struct skb_array *q = band2list(priv, band);
> + struct sk_buff *skb;
>
> - priv->bitmap = 0;
> - qdisc->qstats.backlog = 0;
> - qdisc->q.qlen = 0;
> + while ((skb = skb_array_consume_bh(q)) != NULL)
> + __skb_array_destroy_skb(skb);
Can use regular kfree_skb after dequeue. This skb_array specific
callback probably only exists to match the ptr_ring callback typedef.
> static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb)
> @@ -685,17 +688,40 @@ static int pfifo_fast_dump(struct Qdisc *qdisc, struct
> sk_buff *skb)
>
> static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt)
> {
> - int prio;
> + unsigned int qlen = qdisc_dev(qdisc)->tx_queue_len;
> struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
> + int prio;
> +
> + /* guard against zero length rings */
> + if (!qlen)
> + return -EINVAL;
>
> - for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
> - qdisc_skb_head_init(band2list(priv, prio));
> + for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
> + struct skb_array *q = band2list(priv, prio);
> + int err;
> +
> + err = skb_array_init(q, qlen, GFP_KERNEL);
> + if (err)
> + return -ENOMEM;
This relies on the caller calling ops->destroy on error to free partially
allocated state. For uninitialized bands, that calls spin_lock on an
uninitialized spinlock from skb_array_cleanup -> ptr_ring_cleanup ->
ptr_ring_consume.
> + }
>
> /* Can by-pass the queue discipline */
> qdisc->flags |= TCQ_F_CAN_BYPASS;
> return 0;
> }
>
> +static void pfifo_fast_destroy(struct Qdisc *sch)
> +{
> + struct pfifo_fast_priv *priv = qdisc_priv(sch);
> + int prio;
> +
> + for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
> + struct skb_array *q = band2list(priv, prio);
> +
> + skb_array_cleanup(q);
> + }
> +}
